During a break yesterday after sailing my Starboard iSonic 111, 2008 model, I noticed a small line of water running across the bottom width of my board (board was on its side in direct sunlight).

What I found was a 2.5 cm long, hairline crack in the finish, almost imperceptible. Water was slowing seeping out the crack and running down the board (a dozen drops or so?). I also found a second smaller crack about 15 cm away, but only a couple of drops on the surface.

There is NO damage to the bottom of the board or anywhere for that matter. No dings, scraped, dents, etc. The cracks must be stress related. Also, no bubbling of the skin, or appearance of any delamination. I had to put tape next to the cracks for fear that I could not find them again because they are so fine.

My issue is, what do I have? Just a little water under the skin? a crack that goes through to the foam (hard to believe), what is the next layer below the paint, and what type of repair is needed?

A thin coat of epoxy over the cracks?
Try to cut and peel off the skin (what is, and how thick is the skin) around the crack and fill in with epoxy?
Cut out the damaged part down to the foam and fill in?

Although I don't have real experience on this topic, I read on many other forums that people use super glue for these kind of minor hairline cracks. It will not resist any stress or other structural cracks but it will help prevent water intrusion.

Hi Ken,
Sorry to hear about the cracks.
The only way to be sure exactly what these cracks are is to sand them down until they disappear.
There are many layers of different material in the bottom of your iSonic.
Yours is WOOD construction if I remember correctly.
The paint on the bottom goes on over a thin 0.026" mm wood veneer layer.
The wood veneer layer is saturated in epoxy resin so it's supposed to be fully sealed.
Below the saturated wood layer you will find a layer of thin fiberglass then a layer of hard foam.
If you sand the area of the crack down a bit I suspect you will find that the crack does not extend
below the wood layer and that there may be a little area of the wood that didn't get fully saturated with
resin at the factory.
If you look at "The Board Lady" website, she suggests a special "penetrating resin" for repairs like this
it's thin and made to be easily absorbed by cracks and by unsaturated wood.
If the crack goes deeper, you would need to sand/file/grind it down until it disappears and then rebuild the layers with the same or similar materials.
Might be better use a curved half round diemakers riffler to determine the crack depth as this will put a nice radius on both sides of the crack as it removes the material and will be stronger and easier to fair in when you rebuild it back with penetrating resin and then paint.
Hope this helps,
Roger

Hi again Ken,
Very possibly the issue you have is caused by a localized area of the paint being slightly porous and
the wood underneath being slightly resin starved.
A little water gets through the paint and the wood soaks it up, causing a tiny crack.
It's not structural, and once you seal it you should have no more isses.
Better, I think, to use the hald round riffler to file out the crack so you know you've stopped it, then
seal it up and paint it.
You could simply seal the crack, but you would never know to what depth it leads and if it would cause
some issues down the road if the paint leaks again.
Roger

Here is an update. I started grinding down and found that although the smaller than hair line cracks in the paint were not just superficial, but did go down to the foam in one but not the other. I ground around until those cracks as well as some other cracks running perpendicular from the surface crack were no longer visible. I have two holes, one quarter size and one half dollar size. I let it dry in the sun for a few hours (seems like the wood was damp).

Where the foam was exposed (only in the bigger hole), I filled in with some "chopped up glass fibers" then some epoxy, then a layer of glass more epoxy & another layer of glass & epoxy. The other hole - epoxy, glass and epoxy. Tomorrow, both holes will need to be completely filled with one more layer of glass and epoxy to finish it off. A friend suggested I do it in two sessions since too much epoxy could overheat and cause damage to the foam.

I am sure this will do the trick, but the damage appears to have been the result of several years of pounding in small chop and are stress fractures and not related to any impacts. Hopeful there will be no more problems.

I check the Board Lady web site and didn't find anything similar to my problem, but there were other helpful pieces of information.